Power supply unit



FIG. 1 is a right front top perspective view of the power supply unit showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a front elevation view thereof;

FIG. 6 is a back elevation view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown represent unclaimed subject matter and form no part of the claimed design. 

CLAIM The ornamental design for a power supply unit, as shown. 